Where's the drone coming from?
 

Hi everyone,

I have a 2011 G37 coupe and I've recently installed a Motiv Concept HFC and a Fast Intentions CBE. I had them both installed at the same time, and after a few weeks of driving, I now hear a lot of droning. It is ridiculous, and I was wondering which one (HFC or CBE) is causing this droning so I can swap out the right one. Thoughts appreciated. Thanks

I'm no expert on exhaust but I'd be inclined to think you'd get more drone from the HFC. That's a lot of restriction removed. HFC on stock exhaust or Tanabe Medallion (pretty quiet exhaust, zero drone) is quite loud, as is. Though, they're probably both producing a drone and removing either would likely only reduce but not remove the drone.

I'm not familiar with the Fast Intentions exhaust. The drone wasn't onset?


I drove a stock Q50S that had the "Infiniti Sport Mufflers" (I believe the coupe mufflers fitted to the sedan) and it had so much drone. Of course, a quieter muffler would hush the HFC either way. Could you not try your stock exhaust with the HFC or is it all custom now?

Is your Catback resonated? I had fast intentions resonated hfc & Catback and no drone.

Resonators would def help cut down the drone if you don't have any. I got drone after installing my test pipes, so I had an X-pipe fabricated instead of running a y-pipe and it completely killed off my drone.

Thanks for the thoughts. The CBE is resonated. I don't have the OEM exhaust anymore, but I do have the OEM cats. I was thinking about swapping those back in and hope the droning is more bearable, but figured it's better to get some second opinions.

OEM cats should fix most of your issues... Try that and come back if your still having issues.

just an update, i switched back to the OEM cats a while back and it helped with the droning a lot. I would say 90% of it is gone.